Clarification about the "Sexual Slavery" for Hiroko Tabuchi of NYT

She means Rome Statute of the International Crime Court. In the Article 7, “Crimes against humanity”, it is written

(g) Rape, sexual slavery, enforced prostitution, forced pregnancy, enforced sterilization, or any other form of sexual violence of comparable gravity;

Sexual slavery is a special case of enslavement. Its definition is the following:

“Enslavement” means the exercise of any or all of the powers attaching to the right of ownership over a person and includes the exercise of such power in the course of trafficking in persons, in particular women and children;

It’s human trafficking. If Ms. Tabuchi uses sexual slavery in this sense, it is evident that there was sex slavery in the pacific area during WW2. Many women were sold, bought, and owned by private parties. All historains agree.

The problem is: why does NYT accuse Japanese government for the private sex slavery? It was private because slavery was forbidden by law. Japan has never legalized slavery as the United States did in the Constitution in 1789. In the rule of the ICC, only private people or companies would be prosecuted.

If you would like to accuse the government, you should prove legal enforcement of sex slavery by Japanese government. In the article to correct their articles, Asahi Shimbun confessed

No official documents were found that directly showed forcible taking away by the military on the Korean Peninsula and Taiwan, where the people living there were made “subjects” of the Japanese Empire under Japanese colonial rule. Prostitution agents were prevalent due to the poverty and patriarchal family system.

So it’s clear:

• Private parties were engaged in “sex slavery” i.e. human trafficking in many countries during WW2.
• Japanese government and military managed them, but didn’t enforce slavery. Slavery was forbidden.